The title “On First Contact” sounds slightly extraterrestrial — “Close Encounters of the Camera Kind”? Actually, it relates to one of the most fundamental aspects of photography. The show runs through Jan. 14 at Panopticon Gallery, as does another exhibit, “What I Did on My Summer Vacation.”

Photography is a process, and that process is a progression. A negative inside the camera is exposed to light. A positive image is made from that image in the darkroom. Further positive images — prints — can then be made. Often those prints are worked over: enlarged, cropped, burned, dodged (the terminology is splendid). Some photographers, like Bill Brandt, were famous, or notorious, for how much they’d do to subsequent iterations of their images.

Such worked-over prints differ from that original contact print, which derives its name from how the photographic paper takes up the image from the negative through contact with it. Such prints are the same size as the negative, which means they are notable for their crispness, detailing, and tonal gradations. Multiple contact prints, seen on the same piece of paper, are contact sheets. “On First Contact” consists of more than 60 contact prints and five contact sheets. There’s a triptych, too, by Panopticon owner Jason Landry, no less, of a press conference featuring photographer Vik Muniz.

Since all the images are contact prints, it’s a given that they are all of high visual quality. What’s not a given, and what gives the show its appeal, is how diverse “On First Contact” is. Consider two of the contact sheets. Herb Greene has a dozen portraits of Led Zeppelin, which he shot in San Francisco, in 1969. Hanging nearby is a sheet with a dozen portraits Douglas Prince made of his then fellow Rhode Island School of Design student (and future photography star) Francesca Woodman. She looks unnervingly prim. The same cannot be said for the Zeps.

Several photographers have multiple images in the show. There are 12, for example, from Agnieszka Sosnowska. They’re slightly surreal collisions (glancing blows might be a better term) between self-portraiture and landscape. The fact that Sosnowska took most of them in Iceland, where a slight surrealism is as much a property of the environment as geothermal heat is, might have something to do with this. Then again, she took the most surreal image, which shows her from the waist down standing on the branch of a tree, in Norwell.

ON FIRST CONTACT // WHAT I DID ON MY SUMMER VACATION

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As the title of “To Start a Fire” indicates, Adam Katseff, who has four photographs in the show, takes a very different arboreal approach, as its title suggests. It’s one of the most arresting images in the show. Where flame and energy dominate Katseff’s picture, emptiness defines Neal Rantoul’s two photographs of rooftop parking spaces. They’re such studies in absence — dead space and inactivity — that they seem almost entropic. Yet they are no less striking than Katseff’s burning tree. Here is the wonder of art: that such differing works can have a similar effect.

“What I Did on My Summer Vacation” is a nicely timed title, as leaves begin to fall and the days shorten. So it’s most agreeable to find among these 40 photographs scenes of beach, pool, and playground, as well as Mount Rushmore, Battleship Cove, the National Gallery’s Sainsbury wing (that’s the one Prince Charles dislikes so much), an MBTA bus stop, a mosh pit, and even the surface of the sun (surely, the ne plus ultra of summer places). Brett Henrikson’s shot of a camera pictogram from Death Valley, “In Case You Missed,” is very funny. As for Stefanie Klavens’s
“Malta Drive-In, Malta, N.Y.,” it would suggest that the nights of Malta must be rather wonderful, or at least they are when popcorn and a double feature are involved.

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